This invention relates to a laser device for an endoscope, wherein a light-transmitter is set in the insertion section of an endoscope, a laser beam and guide beam are sent forth by means of the light-transmitter, and a patient's affected spot is medically treated by the laser beam thus guided.
The insertion section of an endoscope generally holds a light-guiding path such as an optical fiber bundle and an image-transmitting path such as an image guide fiber bundle.
Guide light beams transmitted through a light guide fiber bundle, for example, helium-neon laser beam and light beam issued from a xenon lamp are ejected outward from the distal end of an endoscope. An image of an object of observation, for example, a patient's inner coeliac wall illuminated by such guide beams is transmitted through the image guide to the observation section of the endoscope at the proximal end. The coeliac wall is observed through an eyepiece lens system of the observation section. A laser beam transmitter (laser probe) is received in the insertion channel of the endoscope. A medical treatment laser beam supplied from an external infrared laser beam oscillator is ejected from the end portion of the light transmitter for the excision of a patient's coeliac affected spot.
It is known that when rendered morbid, part of an inner coeliac wall presents a different color from the wholesome portions of said coeliac wall. Since, however, a guide light is generally formed of a white ray, a small affected portion of the inner coeliac wall is difficult to be distinguished from the wholesome portions thereof. Therefore, such small affected portion has hitherto beam likely to be overlooked.
The medical treatment laser beam is a colorless ray (infrared ray) or an extremely faint visible ray. Therefore, it is extremely difficult to observe those portions of the coeliac wall which are illuminated by such laser ray in the observation section of the endoscope. The aforesaid guide light beam is used to illuminate a relatively large area of an object of observation independently of a laser beam emitting section. Therefore, difficulties have been experienced in accurately directing laser beams to a patient's affected coeliac spot while looking at the object of observation in the endoscope observation section. Actually therefore, the endoscope operator tries to set a patient's affected coeliac spot in that portion of the view field of the endoscope observation section which is supposedly illuminated by laser beams.